I know this is probably redundant but: Block a Sender in Windows Live Mail
To add a sender to your list of blocked senders in Windows Live Mail or Windows Mail:
- Highlight a message from the undesired sender in the message list.
- Make sure the Home ribbon is active.
- Click the down arrow beneath Junk in the Home ribbon.
- Select Add sender to blocked sender list from the menu.
- Select Add sender's domain to blocked sender list from the menu to block messages not only from this sender but from all addresses at the same domain (what follows the '@' sign).